Guerrilla fighters in Papua's central highlands, who want to free Papua from Indonesia, kidnapped New Zealand pilot Captain Phillip Mehrtens after he landed a commercial plane in the mountainous area of Nduga.

In a new video released on Friday, a visibly emaciated Mehrtens holds the banned Morning Star flag, a symbol of West Papuan independence, and is surrounded by Papuan fighters brandishing what one analyst said were assault rifles manufactured in Indonesia.

Mehrtens is seen talking to the camera, saying the separatists want countries other than Indonesia to engage in dialogue on Papuan independence.

"If it does not happen within two months then they say they will shoot me," Mehrtens says in the video, which was shared by Papuan rebel spokesman Sebby Sambom, and verified by Deka Anwar, an analyst at the Jakarta-based Institute for Policy Analysis of Conflict (IPAC).

The Indonesian foreign ministry and military, and the New Zealand embassy in Jakarta did not immediately respond to requests for comment.

Indonesian authorities have previously said they are prioritising peaceful negotiations to secure the release of the Susi Air pilot, but have struggled to access the isolated and rugged highland terrain.

A low-level but increasingly deadly battle for independence has been waged in resource-rich Papua ever since it was controversially brought under Indonesian control in a vote overseen by the United Nations in 1969.

The conflict has escalated significantly since 2018, with pro-independence fighters mounting deadlier and more frequent attacks, largely because they have managed to procure more sophisticated weapons.

Rumianus Wandikbo of the West Papua National Liberation Army - the armed wing of the Free Papua Movement - called on countries such as New Zealand, Australia and Western nations to kickstart talks with Indonesia and the separatists.

"We do not ask for money ... We really demand our rights for sovereignty," he said in a separate video.

Australian Associated Press